Baby teeth hold clues to the harms of toxic metals for infants — and older kids
Scientists say they also hold the key to figuring out what metals in the environment infants were exposed to — and how they affect not just developing baby brains, but behavior in adolescents.
"It seems like an impossible question to answer," says Dr. Manish Arora, a professor of environmental medicine at the Icahn School of Medicine at Mount Sinai. "Luckily for us, baby teeth are this amazing organ."
He says baby teeth work kind of like tree growth rings. They start to form in utero, beginning in the second trimester. And as they develop, layer by layer, they incorporate trace amounts of metals they're exposed to — in the womb and early life. That's when the brain is most vulnerable to toxic metals.
In a new study in the journal Science Advances, Arora and his colleagues used lasers to decode those layers in the baby teeth shed by 500 children in Mexico City. That allowed them to create a timeline of what neurotoxic metals those children were exposed to, week by week, even before they were born.
Connecting teeth to the brain
The children in the study have been followed since their mothers were pregnant. As the children reached adolescence, the researchers also took detailed behavior assessments for some of the kids and MRI scans of their brains.
While the baby teeth allowed the researchers to figure out the timeline of exposures, the brain scans helped them link those exposures to impacts on brain development, says study co-author Megan Horton, also a professor of environmental medicine at Mount Sinai.
Want the latest stories on the science of healthy living? Subscribe to NPR's Health newsletter.
"Using MRI allows us to look at what those exposures are doing to the brain in terms of its structure, connections and how different areas of the brain communicate," Horton says.
Discussion (0)